Latest GPAK4 mixed-signal FPGA project sees the light - Embedded.com

Latest GPAK4 mixed-signal FPGA project sees the light

I just heard from my chum Wojciech (Wojtek) Rynczuk, who is and embedded software engineer with Rockwell Automation based in Poland. (I'm sorry, I can never hear Rockwell Automation mentioned without being reminded of that classic spoof about the Rockwell Retro Encabulator).

Some time ago, the folks at Silego offered 25 free GPAK4 development kits to whoever could tempt me with the tastiest of tempting ideas for GPAK4-related projects (as you may recall, I tend to think of these little rascals — the GPAK4 chips, not the folks at Silego — as being teeny-tiny mixed-signal FPGAs).


(Source: Silego)

The first project we saw implemented was a multi-peripheral controller by J.R. Stoner. Now we are presented with a rather interesting offering from Wojtek, who has used his GPAK4 development kit to create a light-following device.


(Source: Wojciech Rynczuk)

Wojtek's message to me read as follows:

Hi Max, I'm sorry it took a while before I finally got to the Silego stuff, but I must admit that I am impressed. You can squeeze a lot from those tiny chips. Although they are not applicable to the professional project I'm currently working on, I became familiarized with them and they may be considered in the future. I attach a short PDF description of what I've made. I failed in terms of mechanics (the motor I had on hand turned out to be too weak to carry the stuff and my connections were too short) but I succeeded in terms of Silego exploration (I hope). See the videos referenced below for yourself — just use a little bit of imagination 🙂

What I liked most about the GPAK4 is the reasonable amount of mixed, analog, and digital, resources inside. But the real winner is the GreenPAK development kit. It is awesome. It allows for simulating everything — digital/analog inputs/outputs, where the analog inputs can be driven by the built-in signal generators. Additionally, you can build your devices incrementally; for example, you can connect to signals to some of the physical inputs and outputs while you continue to use the artificial stubs for those signals that are not yet physically realized. It's great!

A small disadvantage is the schematic entry. One must learn a few tricks. E.g., in order to successfully remove a component from a diagram, it is not enough to simply delete it. First, one needs to remove all of its connections; next, reset the component to its default state; and only then can it be easily removed from the schematics. Similarly, even though you might configure the SPI output to pin 10, for example, this connection is not automatically made until you manually reconfigure pin 10 to be a digital output. All of this could be automated. It took me a while before I found out the tricks, and it was driving me crazy at the very beginning. On the other hand, the tool was intuitive enough for me to create the project without reading the manual 🙂

Anyway I posted all of the files (the GreenPAK project, some videos, and some pictures) as my SilegoLight project on GitHub to share it easily with anyone who is interested.

BTW, I liked your article about right whales. I didn't know there left so few of them 🙁 But I am happy to hear about the current trend in population growth.

As always, I'm tremendously impressed with the incredible versatility of these little scamps (once again, I'm talking about the GPAK4 chips, not the folks at Silego, although now I come to think about it…). How about you? Have you worked with the GPAK4 devices yourself, or are you still thinking about dipping your toes in the Silego waters?

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